drivers/scsi/ibmvscsi/ibmvscsi.c

   1 /* ------------------------------------------------------------
   2  * ibmvscsi.c
   3  * (C) Copyright IBM Corporation 1994, 2004
   4  * Authors: Colin DeVilbiss (devilbis@us.ibm.com)
   5  *          Santiago Leon (santil@us.ibm.com)
   6  *          Dave Boutcher (sleddog@us.ibm.com)
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
  21  * USA
  22  *
  23  * ------------------------------------------------------------
  24  * Emulation of a SCSI host adapter for Virtual I/O devices
  25  *
  26  * This driver supports the SCSI adapter implemented by the IBM
  27  * Power5 firmware.  That SCSI adapter is not a physical adapter,
  28  * but allows Linux SCSI peripheral drivers to directly
  29  * access devices in another logical partition on the physical system.
  30  *
  31  * The virtual adapter(s) are present in the open firmware device
  32  * tree just like real adapters.
  33  *
  34  * One of the capabilities provided on these systems is the ability
  35  * to DMA between partitions.  The architecture states that for VSCSI,
  36  * the server side is allowed to DMA to and from the client.  The client
  37  * is never trusted to DMA to or from the server directly.
  38  *
  39  * Messages are sent between partitions on a "Command/Response Queue"
  40  * (CRQ), which is just a buffer of 16 byte entries in the receiver's
  41  * Senders cannot access the buffer directly, but send messages by
  42  * making a hypervisor call and passing in the 16 bytes.  The hypervisor
  43  * puts the message in the next 16 byte space in round-robbin fashion,
  44  * turns on the high order bit of the message (the valid bit), and
  45  * generates an interrupt to the receiver (if interrupts are turned on.)
  46  * The receiver just turns off the valid bit when they have copied out
  47  * the message.
  48  *
  49  * The VSCSI client builds a SCSI Remote Protocol (SRP) Information Unit
  50  * (IU) (as defined in the T10 standard available at www.t10.org), gets
  51  * a DMA address for the message, and sends it to the server as the
  52  * payload of a CRQ message.  The server DMAs the SRP IU and processes it,
  53  * including doing any additional data transfers.  When it is done, it
  54  * DMAs the SRP response back to the same address as the request came from,
  55  * and sends a CRQ message back to inform the client that the request has
  56  * completed.
  57  *
  58  * Note that some of the underlying infrastructure is different between
  59  * machines conforming to the "RS/6000 Platform Architecture" (RPA) and
  60  * the older iSeries hypervisor models.  To support both, some low level
  61  * routines have been broken out into rpa_vscsi.c and iseries_vscsi.c.
  62  * The Makefile should pick one, not two, not zero, of these.
  63  *
  64  * TODO: This is currently pretty tied to the IBM i/pSeries hypervisor
  65  * interfaces.  It would be really nice to abstract this above an RDMA
  66  * layer.
  67  */
  68
  69 #include <linux/module.h>
  70 #include <linux/moduleparam.h>
  71 #include <linux/dma-mapping.h>
  72 #include <linux/delay.h>
  73 #include <linux/of.h>
  74 #include <asm/firmware.h>
  75 #include <asm/vio.h>
  76 #include <asm/firmware.h>
  77 #include <scsi/scsi.h>
  78 #include <scsi/scsi_cmnd.h>
  79 #include <scsi/scsi_host.h>
  80 #include <scsi/scsi_device.h>
  81 #include <scsi/scsi_transport_srp.h>
  82 #include "ibmvscsi.h"
  83
  84 /* The values below are somewhat arbitrary default values, but
  85  * OS/400 will use 3 busses (disks, CDs, tapes, I think.)
  86  * Note that there are 3 bits of channel value, 6 bits of id, and
  87  * 5 bits of LUN.
  88  */
  89 static int max_id = 64;
  90 static int max_channel = 3;
  91 static int init_timeout = 300;
  92 static int login_timeout = 60;
  93 static int info_timeout = 30;
  94 static int abort_timeout = 60;
  95 static int reset_timeout = 60;
  96 static int max_requests = IBMVSCSI_MAX_REQUESTS_DEFAULT;
  97 static int max_events = IBMVSCSI_MAX_REQUESTS_DEFAULT + 2;
  98 static int fast_fail = 1;
  99 static int client_reserve = 1;
 100
 101 static struct scsi_transport_template *ibmvscsi_transport_template;
 102
 103 #define IBMVSCSI_VERSION "1.5.8"
 104
 105 static struct ibmvscsi_ops *ibmvscsi_ops;
 106
 107 MODULE_DESCRIPTION("IBM Virtual SCSI");
 108 MODULE_AUTHOR("Dave Boutcher");
 109 MODULE_LICENSE("GPL");
 110 MODULE_VERSION(IBMVSCSI_VERSION);
 111
 112 module_param_named(max_id, max_id, int, S_IRUGO | S_IWUSR);
 113 MODULE_PARM_DESC(max_id, "Largest ID value for each channel");
 114 module_param_named(max_channel, max_channel, int, S_IRUGO | S_IWUSR);
 115 MODULE_PARM_DESC(max_channel, "Largest channel value");
 116 module_param_named(init_timeout, init_timeout, int, S_IRUGO | S_IWUSR);
 117 MODULE_PARM_DESC(init_timeout, "Initialization timeout in seconds");
 118 module_param_named(max_requests, max_requests, int, S_IRUGO);
 119 MODULE_PARM_DESC(max_requests, "Maximum requests for this adapter");
 120 module_param_named(fast_fail, fast_fail, int, S_IRUGO | S_IWUSR);
 121 MODULE_PARM_DESC(fast_fail, "Enable fast fail. [Default=1]");
 122 module_param_named(client_reserve, client_reserve, int, S_IRUGO );
 123 MODULE_PARM_DESC(client_reserve, "Attempt client managed reserve/release");
 124
 125 /* ------------------------------------------------------------
 126  * Routines for the event pool and event structs
 127  */
 128 /**
 129  * initialize_event_pool: - Allocates and initializes the event pool for a host
 130  * @pool:       event_pool to be initialized
 131  * @size:       Number of events in pool
 132  * @hostdata:   ibmvscsi_host_data who owns the event pool
 133  *
 134  * Returns zero on success.
 135 */
 136 static int initialize_event_pool(struct event_pool *pool,
 137                                  int size, struct ibmvscsi_host_data *hostdata)
 138 {
 139         int i;
 140
 141         pool->size = size;
 142         pool->next = 0;
 143         pool->events = kcalloc(pool->size, sizeof(*pool->events), GFP_KERNEL);
 144         if (!pool->events)
 145                 return -ENOMEM;
 146
 147         pool->iu_storage =
 148             dma_alloc_coherent(hostdata->dev,
 149                                pool->size * sizeof(*pool->iu_storage),
 150                                &pool->iu_token, 0);
 151         if (!pool->iu_storage) {
 152                 kfree(pool->events);
 153                 return -ENOMEM;
 154         }
 155
 156         for (i = 0; i < pool->size; ++i) {
 157                 struct srp_event_struct *evt = &pool->events[i];
 158                 memset(&evt->crq, 0x00, sizeof(evt->crq));
 159                 atomic_set(&evt->free, 1);
 160                 evt->crq.valid = 0x80;
 161                 evt->crq.IU_length = sizeof(*evt->xfer_iu);
 162                 evt->crq.IU_data_ptr = pool->iu_token +
 163                         sizeof(*evt->xfer_iu) * i;
 164                 evt->xfer_iu = pool->iu_storage + i;
 165                 evt->hostdata = hostdata;
 166                 evt->ext_list = NULL;
 167                 evt->ext_list_token = 0;
 168         }
 169
 170         return 0;
 171 }
 172
 173 /**
 174  * release_event_pool: - Frees memory of an event pool of a host
 175  * @pool:       event_pool to be released
 176  * @hostdata:   ibmvscsi_host_data who owns the even pool
 177  *
 178  * Returns zero on success.
 179 */
 180 static void release_event_pool(struct event_pool *pool,
 181                                struct ibmvscsi_host_data *hostdata)
 182 {
 183         int i, in_use = 0;
 184         for (i = 0; i < pool->size; ++i) {
 185                 if (atomic_read(&pool->events[i].free) != 1)
 186                         ++in_use;
 187                 if (pool->events[i].ext_list) {
 188                         dma_free_coherent(hostdata->dev,
 189                                   SG_ALL * sizeof(struct srp_direct_buf),
 190                                   pool->events[i].ext_list,
 191                                   pool->events[i].ext_list_token);
 192                 }
 193         }
 194         if (in_use)
 195                 dev_warn(hostdata->dev, "releasing event pool with %d "
 196                          "events still in use?\n", in_use);
 197         kfree(pool->events);
 198         dma_free_coherent(hostdata->dev,
 199                           pool->size * sizeof(*pool->iu_storage),
 200                           pool->iu_storage, pool->iu_token);
 201 }
 202
 203 /**
 204  * valid_event_struct: - Determines if event is valid.
 205  * @pool:       event_pool that contains the event
 206  * @evt:        srp_event_struct to be checked for validity
 207  *
 208  * Returns zero if event is invalid, one otherwise.
 209 */
 210 static int valid_event_struct(struct event_pool *pool,
 211                                 struct srp_event_struct *evt)
 212 {
 213         int index = evt - pool->events;
 214         if (index < 0 || index >= pool->size)   /* outside of bounds */
 215                 return 0;
 216         if (evt != pool->events + index)        /* unaligned */
 217                 return 0;
 218         return 1;
 219 }
 220
 221 /**
 222  * ibmvscsi_free-event_struct: - Changes status of event to "free"
 223  * @pool:       event_pool that contains the event
 224  * @evt:        srp_event_struct to be modified
 225  *
 226 */
 227 static void free_event_struct(struct event_pool *pool,
 228                                        struct srp_event_struct *evt)
 229 {
 230         if (!valid_event_struct(pool, evt)) {
 231                 dev_err(evt->hostdata->dev, "Freeing invalid event_struct %p "
 232                         "(not in pool %p)\n", evt, pool->events);
 233                 return;
 234         }
 235         if (atomic_inc_return(&evt->free) != 1) {
 236                 dev_err(evt->hostdata->dev, "Freeing event_struct %p "
 237                         "which is not in use!\n", evt);
 238                 return;
 239         }
 240 }
 241
 242 /**
 243  * get_evt_struct: - Gets the next free event in pool
 244  * @pool:       event_pool that contains the events to be searched
 245  *
 246  * Returns the next event in "free" state, and NULL if none are free.
 247  * Note that no synchronization is done here, we assume the host_lock
 248  * will syncrhonze things.
 249 */
 250 static struct srp_event_struct *get_event_struct(struct event_pool *pool)
 251 {
 252         int i;
 253         int poolsize = pool->size;
 254         int offset = pool->next;
 255
 256         for (i = 0; i < poolsize; i++) {
 257                 offset = (offset + 1) % poolsize;
 258                 if (!atomic_dec_if_positive(&pool->events[offset].free)) {
 259                         pool->next = offset;
 260                         return &pool->events[offset];
 261                 }
 262         }
 263
 264         printk(KERN_ERR "ibmvscsi: found no event struct in pool!\n");
 265         return NULL;
 266 }
 267
 268 /**
 269  * init_event_struct: Initialize fields in an event struct that are always
 270  *                    required.
 271  * @evt:        The event
 272  * @done:       Routine to call when the event is responded to
 273  * @format:     SRP or MAD format
 274  * @timeout:    timeout value set in the CRQ
 275  */
 276 static void init_event_struct(struct srp_event_struct *evt_struct,
 277                               void (*done) (struct srp_event_struct *),
 278                               u8 format,
 279                               int timeout)
 280 {
 281         evt_struct->cmnd = NULL;
 282         evt_struct->cmnd_done = NULL;
 283         evt_struct->sync_srp = NULL;
 284         evt_struct->crq.format = format;
 285         evt_struct->crq.timeout = timeout;
 286         evt_struct->done = done;
 287 }
 288
 289 /* ------------------------------------------------------------
 290  * Routines for receiving SCSI responses from the hosting partition
 291  */
 292
 293 /**
 294  * set_srp_direction: Set the fields in the srp related to data
 295  *     direction and number of buffers based on the direction in
 296  *     the scsi_cmnd and the number of buffers
 297  */
 298 static void set_srp_direction(struct scsi_cmnd *cmd,
 299                               struct srp_cmd *srp_cmd,
 300                               int numbuf)
 301 {
 302         u8 fmt;
 303
 304         if (numbuf == 0)
 305                 return;
 306
 307         if (numbuf == 1)
 308                 fmt = SRP_DATA_DESC_DIRECT;
 309         else {
 310                 fmt = SRP_DATA_DESC_INDIRECT;
 311                 numbuf = min(numbuf, MAX_INDIRECT_BUFS);
 312
 313                 if (cmd->sc_data_direction == DMA_TO_DEVICE)
 314                         srp_cmd->data_out_desc_cnt = numbuf;
 315                 else
 316                         srp_cmd->data_in_desc_cnt = numbuf;
 317         }
 318
 319         if (cmd->sc_data_direction == DMA_TO_DEVICE)
 320                 srp_cmd->buf_fmt = fmt << 4;
 321         else
 322                 srp_cmd->buf_fmt = fmt;
 323 }
 324
 325 static void unmap_sg_list(int num_entries,
 326                 struct device *dev,
 327                 struct srp_direct_buf *md)
 328 {
 329         int i;
 330
 331         for (i = 0; i < num_entries; ++i)
 332                 dma_unmap_single(dev, md[i].va, md[i].len, DMA_BIDIRECTIONAL);
 333 }
 334
 335 /**
 336  * unmap_cmd_data: - Unmap data pointed in srp_cmd based on the format
 337  * @cmd:        srp_cmd whose additional_data member will be unmapped
 338  * @dev:        device for which the memory is mapped
 339  *
 340 */
 341 static void unmap_cmd_data(struct srp_cmd *cmd,
 342                            struct srp_event_struct *evt_struct,
 343                            struct device *dev)
 344 {
 345         u8 out_fmt, in_fmt;
 346
 347         out_fmt = cmd->buf_fmt >> 4;
 348         in_fmt = cmd->buf_fmt & ((1U << 4) - 1);
 349
 350         if (out_fmt == SRP_NO_DATA_DESC && in_fmt == SRP_NO_DATA_DESC)
 351                 return;
 352         else if (out_fmt == SRP_DATA_DESC_DIRECT ||
 353                  in_fmt == SRP_DATA_DESC_DIRECT) {
 354                 struct srp_direct_buf *data =
 355                         (struct srp_direct_buf *) cmd->add_data;
 356                 dma_unmap_single(dev, data->va, data->len, DMA_BIDIRECTIONAL);
 357         } else {
 358                 struct srp_indirect_buf *indirect =
 359                         (struct srp_indirect_buf *) cmd->add_data;
 360                 int num_mapped = indirect->table_desc.len /
 361                         sizeof(struct srp_direct_buf);
 362
 363                 if (num_mapped <= MAX_INDIRECT_BUFS) {
 364                         unmap_sg_list(num_mapped, dev, &indirect->desc_list[0]);
 365                         return;
 366                 }
 367
 368                 unmap_sg_list(num_mapped, dev, evt_struct->ext_list);
 369         }
 370 }
 371
 372 static int map_sg_list(struct scsi_cmnd *cmd, int nseg,
 373                        struct srp_direct_buf *md)
 374 {
 375         int i;
 376         struct scatterlist *sg;
 377         u64 total_length = 0;
 378
 379         scsi_for_each_sg(cmd, sg, nseg, i) {
 380                 struct srp_direct_buf *descr = md + i;
 381                 descr->va = sg_dma_address(sg);
 382                 descr->len = sg_dma_len(sg);
 383                 descr->key = 0;
 384                 total_length += sg_dma_len(sg);
 385         }
 386         return total_length;
 387 }
 388
 389 /**
 390  * map_sg_data: - Maps dma for a scatterlist and initializes decriptor fields
 391  * @cmd:        Scsi_Cmnd with the scatterlist
 392  * @srp_cmd:    srp_cmd that contains the memory descriptor
 393  * @dev:        device for which to map dma memory
 394  *
 395  * Called by map_data_for_srp_cmd() when building srp cmd from scsi cmd.
 396  * Returns 1 on success.
 397 */
 398 static int map_sg_data(struct scsi_cmnd *cmd,
 399                        struct srp_event_struct *evt_struct,
 400                        struct srp_cmd *srp_cmd, struct device *dev)
 401 {
 402
 403         int sg_mapped;
 404         u64 total_length = 0;
 405         struct srp_direct_buf *data =
 406                 (struct srp_direct_buf *) srp_cmd->add_data;
 407         struct srp_indirect_buf *indirect =
 408                 (struct srp_indirect_buf *) data;
 409
 410         sg_mapped = scsi_dma_map(cmd);
 411         if (!sg_mapped)
 412                 return 1;
 413         else if (sg_mapped < 0)
 414                 return 0;
 415
 416         set_srp_direction(cmd, srp_cmd, sg_mapped);
 417
 418         /* special case; we can use a single direct descriptor */
 419         if (sg_mapped == 1) {
 420                 map_sg_list(cmd, sg_mapped, data);
 421                 return 1;
 422         }
 423
 424         indirect->table_desc.va = 0;
 425         indirect->table_desc.len = sg_mapped * sizeof(struct srp_direct_buf);
 426         indirect->table_desc.key = 0;
 427
 428         if (sg_mapped <= MAX_INDIRECT_BUFS) {
 429                 total_length = map_sg_list(cmd, sg_mapped,
 430                                            &indirect->desc_list[0]);
 431                 indirect->len = total_length;
 432                 return 1;
 433         }
 434
 435         /* get indirect table */
 436         if (!evt_struct->ext_list) {
 437                 evt_struct->ext_list = (struct srp_direct_buf *)
 438                         dma_alloc_coherent(dev,
 439                                            SG_ALL * sizeof(struct srp_direct_buf),
 440                                            &evt_struct->ext_list_token, 0);
 441                 if (!evt_struct->ext_list) {
 442                         if (!firmware_has_feature(FW_FEATURE_CMO))
 443                                 sdev_printk(KERN_ERR, cmd->device,
 444                                             "Can't allocate memory "
 445                                             "for indirect table\n");
 446                         scsi_dma_unmap(cmd);
 447                         return 0;
 448                 }
 449         }
 450
 451         total_length = map_sg_list(cmd, sg_mapped, evt_struct->ext_list);
 452
 453         indirect->len = total_length;
 454         indirect->table_desc.va = evt_struct->ext_list_token;
 455         indirect->table_desc.len = sg_mapped * sizeof(indirect->desc_list[0]);
 456         memcpy(indirect->desc_list, evt_struct->ext_list,
 457                MAX_INDIRECT_BUFS * sizeof(struct srp_direct_buf));
 458         return 1;
 459 }
 460
 461 /**
 462  * map_data_for_srp_cmd: - Calls functions to map data for srp cmds
 463  * @cmd:        struct scsi_cmnd with the memory to be mapped
 464  * @srp_cmd:    srp_cmd that contains the memory descriptor
 465  * @dev:        dma device for which to map dma memory
 466  *
 467  * Called by scsi_cmd_to_srp_cmd() when converting scsi cmds to srp cmds
 468  * Returns 1 on success.
 469 */
 470 static int map_data_for_srp_cmd(struct scsi_cmnd *cmd,
 471                                 struct srp_event_struct *evt_struct,
 472                                 struct srp_cmd *srp_cmd, struct device *dev)
 473 {
 474         switch (cmd->sc_data_direction) {
 475         case DMA_FROM_DEVICE:
 476         case DMA_TO_DEVICE:
 477                 break;
 478         case DMA_NONE:
 479                 return 1;
 480         case DMA_BIDIRECTIONAL:
 481                 sdev_printk(KERN_ERR, cmd->device,
 482                             "Can't map DMA_BIDIRECTIONAL to read/write\n");
 483                 return 0;
 484         default:
 485                 sdev_printk(KERN_ERR, cmd->device,
 486                             "Unknown data direction 0x%02x; can't map!\n",
 487                             cmd->sc_data_direction);
 488                 return 0;
 489         }
 490
 491         return map_sg_data(cmd, evt_struct, srp_cmd, dev);
 492 }
 493
 494 /**
 495  * purge_requests: Our virtual adapter just shut down.  purge any sent requests
 496  * @hostdata:    the adapter
 497  */
 498 static void purge_requests(struct ibmvscsi_host_data *hostdata, int error_code)
 499 {
 500         struct srp_event_struct *tmp_evt, *pos;
 501         unsigned long flags;
 502
 503         spin_lock_irqsave(hostdata->host->host_lock, flags);
 504         list_for_each_entry_safe(tmp_evt, pos, &hostdata->sent, list) {
 505                 list_del(&tmp_evt->list);
 506                 del_timer(&tmp_evt->timer);
 507                 if (tmp_evt->cmnd) {
 508                         tmp_evt->cmnd->result = (error_code << 16);
 509                         unmap_cmd_data(&tmp_evt->iu.srp.cmd,
 510                                        tmp_evt,
 511                                        tmp_evt->hostdata->dev);
 512                         if (tmp_evt->cmnd_done)
 513                                 tmp_evt->cmnd_done(tmp_evt->cmnd);
 514                 } else if (tmp_evt->done)
 515                         tmp_evt->done(tmp_evt);
 516                 free_event_struct(&tmp_evt->hostdata->pool, tmp_evt);
 517         }
 518         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
 519 }
 520
 521 /**
 522  * ibmvscsi_reset_host - Reset the connection to the server
 523  * @hostdata:   struct ibmvscsi_host_data to reset
 524 */
 525 static void ibmvscsi_reset_host(struct ibmvscsi_host_data *hostdata)
 526 {
 527         scsi_block_requests(hostdata->host);
 528         atomic_set(&hostdata->request_limit, 0);
 529
 530         purge_requests(hostdata, DID_ERROR);
 531         if ((ibmvscsi_ops->reset_crq_queue(&hostdata->queue, hostdata)) ||
 532             (ibmvscsi_ops->send_crq(hostdata, 0xC001000000000000LL, 0)) ||
 533             (vio_enable_interrupts(to_vio_dev(hostdata->dev)))) {
 534                 atomic_set(&hostdata->request_limit, -1);
 535                 dev_err(hostdata->dev, "error after reset\n");
 536         }
 537
 538         scsi_unblock_requests(hostdata->host);
 539 }
 540
 541 /**
 542  * ibmvscsi_timeout - Internal command timeout handler
 543  * @evt_struct: struct srp_event_struct that timed out
 544  *
 545  * Called when an internally generated command times out
 546 */
 547 static void ibmvscsi_timeout(struct srp_event_struct *evt_struct)
 548 {
 549         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
 550
 551         dev_err(hostdata->dev, "Command timed out (%x). Resetting connection\n",
 552                 evt_struct->iu.srp.cmd.opcode);
 553
 554         ibmvscsi_reset_host(hostdata);
 555 }
 556
 557
 558 /* ------------------------------------------------------------
 559  * Routines for sending and receiving SRPs
 560  */
 561 /**
 562  * ibmvscsi_send_srp_event: - Transforms event to u64 array and calls send_crq()
 563  * @evt_struct: evt_struct to be sent
 564  * @hostdata:   ibmvscsi_host_data of host
 565  * @timeout:    timeout in seconds - 0 means do not time command
 566  *
 567  * Returns the value returned from ibmvscsi_send_crq(). (Zero for success)
 568  * Note that this routine assumes that host_lock is held for synchronization
 569 */
 570 static int ibmvscsi_send_srp_event(struct srp_event_struct *evt_struct,
 571                                    struct ibmvscsi_host_data *hostdata,
 572                                    unsigned long timeout)
 573 {
 574         u64 *crq_as_u64 = (u64 *) &evt_struct->crq;
 575         int request_status = 0;
 576         int rc;
 577
 578         /* If we have exhausted our request limit, just fail this request,
 579          * unless it is for a reset or abort.
 580          * Note that there are rare cases involving driver generated requests
 581          * (such as task management requests) that the mid layer may think we
 582          * can handle more requests (can_queue) when we actually can't
 583          */
 584         if (evt_struct->crq.format == VIOSRP_SRP_FORMAT) {
 585                 request_status =
 586                         atomic_dec_if_positive(&hostdata->request_limit);
 587                 /* If request limit was -1 when we started, it is now even
 588                  * less than that
 589                  */
 590                 if (request_status < -1)
 591                         goto send_error;
 592                 /* Otherwise, we may have run out of requests. */
 593                 /* If request limit was 0 when we started the adapter is in the
 594                  * process of performing a login with the server adapter, or
 595                  * we may have run out of requests.
 596                  */
 597                 else if (request_status == -1 &&
 598                          evt_struct->iu.srp.login_req.opcode != SRP_LOGIN_REQ)
 599                         goto send_busy;
 600                 /* Abort and reset calls should make it through.
 601                  * Nothing except abort and reset should use the last two
 602                  * slots unless we had two or less to begin with.
 603                  */
 604                 else if (request_status < 2 &&
 605                          evt_struct->iu.srp.cmd.opcode != SRP_TSK_MGMT) {
 606                         /* In the case that we have less than two requests
 607                          * available, check the server limit as a combination
 608                          * of the request limit and the number of requests
 609                          * in-flight (the size of the send list).  If the
 610                          * server limit is greater than 2, return busy so
 611                          * that the last two are reserved for reset and abort.
 612                          */
 613                         int server_limit = request_status;
 614                         struct srp_event_struct *tmp_evt;
 615
 616                         list_for_each_entry(tmp_evt, &hostdata->sent, list) {
 617                                 server_limit++;
 618                         }
 619
 620                         if (server_limit > 2)
 621                                 goto send_busy;
 622                 }
 623         }
 624
 625         /* Copy the IU into the transfer area */
 626         *evt_struct->xfer_iu = evt_struct->iu;
 627         evt_struct->xfer_iu->srp.rsp.tag = (u64)evt_struct;
 628
 629         /* Add this to the sent list.  We need to do this
 630          * before we actually send
 631          * in case it comes back REALLY fast
 632          */
 633         list_add_tail(&evt_struct->list, &hostdata->sent);
 634
 635         init_timer(&evt_struct->timer);
 636         if (timeout) {
 637                 evt_struct->timer.data = (unsigned long) evt_struct;
 638                 evt_struct->timer.expires = jiffies + (timeout * HZ);
 639                 evt_struct->timer.function = (void (*)(unsigned long))ibmvscsi_timeout;
 640                 add_timer(&evt_struct->timer);
 641         }
 642
 643         if ((rc =
 644              ibmvscsi_ops->send_crq(hostdata, crq_as_u64[0], crq_as_u64[1])) != 0) {
 645                 list_del(&evt_struct->list);
 646                 del_timer(&evt_struct->timer);
 647
 648                 /* If send_crq returns H_CLOSED, return SCSI_MLQUEUE_HOST_BUSY.
 649                  * Firmware will send a CRQ with a transport event (0xFF) to
 650                  * tell this client what has happened to the transport.  This
 651                  * will be handled in ibmvscsi_handle_crq()
 652                  */
 653                 if (rc == H_CLOSED) {
 654                         dev_warn(hostdata->dev, "send warning. "
 655                                  "Receive queue closed, will retry.\n");
 656                         goto send_busy;
 657                 }
 658                 dev_err(hostdata->dev, "send error %d\n", rc);
 659                 atomic_inc(&hostdata->request_limit);
 660                 goto send_error;
 661         }
 662
 663         return 0;
 664
 665  send_busy:
 666         unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev);
 667
 668         free_event_struct(&hostdata->pool, evt_struct);
 669         if (request_status != -1)
 670                 atomic_inc(&hostdata->request_limit);
 671         return SCSI_MLQUEUE_HOST_BUSY;
 672
 673  send_error:
 674         unmap_cmd_data(&evt_struct->iu.srp.cmd, evt_struct, hostdata->dev);
 675
 676         if (evt_struct->cmnd != NULL) {
 677                 evt_struct->cmnd->result = DID_ERROR << 16;
 678                 evt_struct->cmnd_done(evt_struct->cmnd);
 679         } else if (evt_struct->done)
 680                 evt_struct->done(evt_struct);
 681
 682         free_event_struct(&hostdata->pool, evt_struct);
 683         return 0;
 684 }
 685
 686 /**
 687  * handle_cmd_rsp: -  Handle responses from commands
 688  * @evt_struct: srp_event_struct to be handled
 689  *
 690  * Used as a callback by when sending scsi cmds.
 691  * Gets called by ibmvscsi_handle_crq()
 692 */
 693 static void handle_cmd_rsp(struct srp_event_struct *evt_struct)
 694 {
 695         struct srp_rsp *rsp = &evt_struct->xfer_iu->srp.rsp;
 696         struct scsi_cmnd *cmnd = evt_struct->cmnd;
 697
 698         if (unlikely(rsp->opcode != SRP_RSP)) {
 699                 if (printk_ratelimit())
 700                         dev_warn(evt_struct->hostdata->dev,
 701                                  "bad SRP RSP type %d\n", rsp->opcode);
 702         }
 703
 704         if (cmnd) {
 705                 cmnd->result |= rsp->status;
 706                 if (((cmnd->result >> 1) & 0x1f) == CHECK_CONDITION)
 707                         memcpy(cmnd->sense_buffer,
 708                                rsp->data,
 709                                rsp->sense_data_len);
 710                 unmap_cmd_data(&evt_struct->iu.srp.cmd,
 711                                evt_struct,
 712                                evt_struct->hostdata->dev);
 713
 714                 if (rsp->flags & SRP_RSP_FLAG_DOOVER)
 715                         scsi_set_resid(cmnd, rsp->data_out_res_cnt);
 716                 else if (rsp->flags & SRP_RSP_FLAG_DIOVER)
 717                         scsi_set_resid(cmnd, rsp->data_in_res_cnt);
 718         }
 719
 720         if (evt_struct->cmnd_done)
 721                 evt_struct->cmnd_done(cmnd);
 722 }
 723
 724 /**
 725  * lun_from_dev: - Returns the lun of the scsi device
 726  * @dev:        struct scsi_device
 727  *
 728 */
 729 static inline u16 lun_from_dev(struct scsi_device *dev)
 730 {
 731         return (0x2 << 14) | (dev->id << 8) | (dev->channel << 5) | dev->lun;
 732 }
 733
 734 /**
 735  * ibmvscsi_queue: - The queuecommand function of the scsi template
 736  * @cmd:        struct scsi_cmnd to be executed
 737  * @done:       Callback function to be called when cmd is completed
 738 */
 739 static int ibmvscsi_queuecommand(struct scsi_cmnd *cmnd,
 740                                  void (*done) (struct scsi_cmnd *))
 741 {
 742         struct srp_cmd *srp_cmd;
 743         struct srp_event_struct *evt_struct;
 744         struct srp_indirect_buf *indirect;
 745         struct ibmvscsi_host_data *hostdata = shost_priv(cmnd->device->host);
 746         u16 lun = lun_from_dev(cmnd->device);
 747         u8 out_fmt, in_fmt;
 748
 749         cmnd->result = (DID_OK << 16);
 750         evt_struct = get_event_struct(&hostdata->pool);
 751         if (!evt_struct)
 752                 return SCSI_MLQUEUE_HOST_BUSY;
 753
 754         /* Set up the actual SRP IU */
 755         srp_cmd = &evt_struct->iu.srp.cmd;
 756         memset(srp_cmd, 0x00, SRP_MAX_IU_LEN);
 757         srp_cmd->opcode = SRP_CMD;
 758         memcpy(srp_cmd->cdb, cmnd->cmnd, sizeof(srp_cmd->cdb));
 759         srp_cmd->lun = ((u64) lun) << 48;
 760
 761         if (!map_data_for_srp_cmd(cmnd, evt_struct, srp_cmd, hostdata->dev)) {
 762                 if (!firmware_has_feature(FW_FEATURE_CMO))
 763                         sdev_printk(KERN_ERR, cmnd->device,
 764                                     "couldn't convert cmd to srp_cmd\n");
 765                 free_event_struct(&hostdata->pool, evt_struct);
 766                 return SCSI_MLQUEUE_HOST_BUSY;
 767         }
 768
 769         init_event_struct(evt_struct,
 770                           handle_cmd_rsp,
 771                           VIOSRP_SRP_FORMAT,
 772                           cmnd->request->timeout/HZ);
 773
 774         evt_struct->cmnd = cmnd;
 775         evt_struct->cmnd_done = done;
 776
 777         /* Fix up dma address of the buffer itself */
 778         indirect = (struct srp_indirect_buf *) srp_cmd->add_data;
 779         out_fmt = srp_cmd->buf_fmt >> 4;
 780         in_fmt = srp_cmd->buf_fmt & ((1U << 4) - 1);
 781         if ((in_fmt == SRP_DATA_DESC_INDIRECT ||
 782              out_fmt == SRP_DATA_DESC_INDIRECT) &&
 783             indirect->table_desc.va == 0) {
 784                 indirect->table_desc.va = evt_struct->crq.IU_data_ptr +
 785                         offsetof(struct srp_cmd, add_data) +
 786                         offsetof(struct srp_indirect_buf, desc_list);
 787         }
 788
 789         return ibmvscsi_send_srp_event(evt_struct, hostdata, 0);
 790 }
 791
 792 /* ------------------------------------------------------------
 793  * Routines for driver initialization
 794  */
 795
 796 /**
 797  * map_persist_bufs: - Pre-map persistent data for adapter logins
 798  * @hostdata:   ibmvscsi_host_data of host
 799  *
 800  * Map the capabilities and adapter info DMA buffers to avoid runtime failures.
 801  * Return 1 on error, 0 on success.
 802  */
 803 static int map_persist_bufs(struct ibmvscsi_host_data *hostdata)
 804 {
 805
 806         hostdata->caps_addr = dma_map_single(hostdata->dev, &hostdata->caps,
 807                                              sizeof(hostdata->caps), DMA_BIDIRECTIONAL);
 808
 809         if (dma_mapping_error(hostdata->dev, hostdata->caps_addr)) {
 810                 dev_err(hostdata->dev, "Unable to map capabilities buffer!\n");
 811                 return 1;
 812         }
 813
 814         hostdata->adapter_info_addr = dma_map_single(hostdata->dev,
 815                                                      &hostdata->madapter_info,
 816                                                      sizeof(hostdata->madapter_info),
 817                                                      DMA_BIDIRECTIONAL);
 818         if (dma_mapping_error(hostdata->dev, hostdata->adapter_info_addr)) {
 819                 dev_err(hostdata->dev, "Unable to map adapter info buffer!\n");
 820                 dma_unmap_single(hostdata->dev, hostdata->caps_addr,
 821                                  sizeof(hostdata->caps), DMA_BIDIRECTIONAL);
 822                 return 1;
 823         }
 824
 825         return 0;
 826 }
 827
 828 /**
 829  * unmap_persist_bufs: - Unmap persistent data needed for adapter logins
 830  * @hostdata:   ibmvscsi_host_data of host
 831  *
 832  * Unmap the capabilities and adapter info DMA buffers
 833  */
 834 static void unmap_persist_bufs(struct ibmvscsi_host_data *hostdata)
 835 {
 836         dma_unmap_single(hostdata->dev, hostdata->caps_addr,
 837                          sizeof(hostdata->caps), DMA_BIDIRECTIONAL);
 838
 839         dma_unmap_single(hostdata->dev, hostdata->adapter_info_addr,
 840                          sizeof(hostdata->madapter_info), DMA_BIDIRECTIONAL);
 841 }
 842
 843 /**
 844  * login_rsp: - Handle response to SRP login request
 845  * @evt_struct: srp_event_struct with the response
 846  *
 847  * Used as a "done" callback by when sending srp_login. Gets called
 848  * by ibmvscsi_handle_crq()
 849 */
 850 static void login_rsp(struct srp_event_struct *evt_struct)
 851 {
 852         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
 853         switch (evt_struct->xfer_iu->srp.login_rsp.opcode) {
 854         case SRP_LOGIN_RSP:     /* it worked! */
 855                 break;
 856         case SRP_LOGIN_REJ:     /* refused! */
 857                 dev_info(hostdata->dev, "SRP_LOGIN_REJ reason %u\n",
 858                          evt_struct->xfer_iu->srp.login_rej.reason);
 859                 /* Login failed.  */
 860                 atomic_set(&hostdata->request_limit, -1);
 861                 return;
 862         default:
 863                 dev_err(hostdata->dev, "Invalid login response typecode 0x%02x!\n",
 864                         evt_struct->xfer_iu->srp.login_rsp.opcode);
 865                 /* Login failed.  */
 866                 atomic_set(&hostdata->request_limit, -1);
 867                 return;
 868         }
 869
 870         dev_info(hostdata->dev, "SRP_LOGIN succeeded\n");
 871         hostdata->client_migrated = 0;
 872
 873         /* Now we know what the real request-limit is.
 874          * This value is set rather than added to request_limit because
 875          * request_limit could have been set to -1 by this client.
 876          */
 877         atomic_set(&hostdata->request_limit,
 878                    evt_struct->xfer_iu->srp.login_rsp.req_lim_delta);
 879
 880         /* If we had any pending I/Os, kick them */
 881         scsi_unblock_requests(hostdata->host);
 882 }
 883
 884 /**
 885  * send_srp_login: - Sends the srp login
 886  * @hostdata:   ibmvscsi_host_data of host
 887  *
 888  * Returns zero if successful.
 889 */
 890 static int send_srp_login(struct ibmvscsi_host_data *hostdata)
 891 {
 892         int rc;
 893         unsigned long flags;
 894         struct srp_login_req *login;
 895         struct srp_event_struct *evt_struct = get_event_struct(&hostdata->pool);
 896
 897         BUG_ON(!evt_struct);
 898         init_event_struct(evt_struct, login_rsp,
 899                           VIOSRP_SRP_FORMAT, login_timeout);
 900
 901         login = &evt_struct->iu.srp.login_req;
 902         memset(login, 0, sizeof(*login));
 903         login->opcode = SRP_LOGIN_REQ;
 904         login->req_it_iu_len = sizeof(union srp_iu);
 905         login->req_buf_fmt = SRP_BUF_FORMAT_DIRECT | SRP_BUF_FORMAT_INDIRECT;
 906
 907         spin_lock_irqsave(hostdata->host->host_lock, flags);
 908         /* Start out with a request limit of 0, since this is negotiated in
 909          * the login request we are just sending and login requests always
 910          * get sent by the driver regardless of request_limit.
 911          */
 912         atomic_set(&hostdata->request_limit, 0);
 913
 914         rc = ibmvscsi_send_srp_event(evt_struct, hostdata, login_timeout * 2);
 915         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
 916         dev_info(hostdata->dev, "sent SRP login\n");
 917         return rc;
 918 };
 919
 920 /**
 921  * capabilities_rsp: - Handle response to MAD adapter capabilities request
 922  * @evt_struct: srp_event_struct with the response
 923  *
 924  * Used as a "done" callback by when sending adapter_info.
 925  */
 926 static void capabilities_rsp(struct srp_event_struct *evt_struct)
 927 {
 928         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
 929
 930         if (evt_struct->xfer_iu->mad.capabilities.common.status) {
 931                 dev_err(hostdata->dev, "error 0x%X getting capabilities info\n",
 932                         evt_struct->xfer_iu->mad.capabilities.common.status);
 933         } else {
 934                 if (hostdata->caps.migration.common.server_support != SERVER_SUPPORTS_CAP)
 935                         dev_info(hostdata->dev, "Partition migration not supported\n");
 936
 937                 if (client_reserve) {
 938                         if (hostdata->caps.reserve.common.server_support ==
 939                             SERVER_SUPPORTS_CAP)
 940                                 dev_info(hostdata->dev, "Client reserve enabled\n");
 941                         else
 942                                 dev_info(hostdata->dev, "Client reserve not supported\n");
 943                 }
 944         }
 945
 946         send_srp_login(hostdata);
 947 }
 948
 949 /**
 950  * send_mad_capabilities: - Sends the mad capabilities request
 951  *      and stores the result so it can be retrieved with
 952  * @hostdata:   ibmvscsi_host_data of host
 953  */
 954 static void send_mad_capabilities(struct ibmvscsi_host_data *hostdata)
 955 {
 956         struct viosrp_capabilities *req;
 957         struct srp_event_struct *evt_struct;
 958         unsigned long flags;
 959         struct device_node *of_node = hostdata->dev->archdata.of_node;
 960         const char *location;
 961
 962         evt_struct = get_event_struct(&hostdata->pool);
 963         BUG_ON(!evt_struct);
 964
 965         init_event_struct(evt_struct, capabilities_rsp,
 966                           VIOSRP_MAD_FORMAT, info_timeout);
 967
 968         req = &evt_struct->iu.mad.capabilities;
 969         memset(req, 0, sizeof(*req));
 970
 971         hostdata->caps.flags = CAP_LIST_SUPPORTED;
 972         if (hostdata->client_migrated)
 973                 hostdata->caps.flags |= CLIENT_MIGRATED;
 974
 975         strncpy(hostdata->caps.name, dev_name(&hostdata->host->shost_gendev),
 976                 sizeof(hostdata->caps.name));
 977         hostdata->caps.name[sizeof(hostdata->caps.name) - 1] = '\0';
 978
 979         location = of_get_property(of_node, "ibm,loc-code", NULL);
 980         location = location ? location : dev_name(hostdata->dev);
 981         strncpy(hostdata->caps.loc, location, sizeof(hostdata->caps.loc));
 982         hostdata->caps.loc[sizeof(hostdata->caps.loc) - 1] = '\0';
 983
 984         req->common.type = VIOSRP_CAPABILITIES_TYPE;
 985         req->buffer = hostdata->caps_addr;
 986
 987         hostdata->caps.migration.common.cap_type = MIGRATION_CAPABILITIES;
 988         hostdata->caps.migration.common.length = sizeof(hostdata->caps.migration);
 989         hostdata->caps.migration.common.server_support = SERVER_SUPPORTS_CAP;
 990         hostdata->caps.migration.ecl = 1;
 991
 992         if (client_reserve) {
 993                 hostdata->caps.reserve.common.cap_type = RESERVATION_CAPABILITIES;
 994                 hostdata->caps.reserve.common.length = sizeof(hostdata->caps.reserve);
 995                 hostdata->caps.reserve.common.server_support = SERVER_SUPPORTS_CAP;
 996                 hostdata->caps.reserve.type = CLIENT_RESERVE_SCSI_2;
 997                 req->common.length = sizeof(hostdata->caps);
 998         } else
 999                 req->common.length = sizeof(hostdata->caps) - sizeof(hostdata->caps.reserve);
1000
1001         spin_lock_irqsave(hostdata->host->host_lock, flags);
1002         if (ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2))
1003                 dev_err(hostdata->dev, "couldn't send CAPABILITIES_REQ!\n");
1004         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1005 };
1006
1007 /**
1008  * fast_fail_rsp: - Handle response to MAD enable fast fail
1009  * @evt_struct: srp_event_struct with the response
1010  *
1011  * Used as a "done" callback by when sending enable fast fail. Gets called
1012  * by ibmvscsi_handle_crq()
1013  */
1014 static void fast_fail_rsp(struct srp_event_struct *evt_struct)
1015 {
1016         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
1017         u8 status = evt_struct->xfer_iu->mad.fast_fail.common.status;
1018
1019         if (status == VIOSRP_MAD_NOT_SUPPORTED)
1020                 dev_err(hostdata->dev, "fast_fail not supported in server\n");
1021         else if (status == VIOSRP_MAD_FAILED)
1022                 dev_err(hostdata->dev, "fast_fail request failed\n");
1023         else if (status != VIOSRP_MAD_SUCCESS)
1024                 dev_err(hostdata->dev, "error 0x%X enabling fast_fail\n", status);
1025
1026         send_mad_capabilities(hostdata);
1027 }
1028
1029 /**
1030  * init_host - Start host initialization
1031  * @hostdata:   ibmvscsi_host_data of host
1032  *
1033  * Returns zero if successful.
1034  */
1035 static int enable_fast_fail(struct ibmvscsi_host_data *hostdata)
1036 {
1037         int rc;
1038         unsigned long flags;
1039         struct viosrp_fast_fail *fast_fail_mad;
1040         struct srp_event_struct *evt_struct;
1041
1042         if (!fast_fail) {
1043                 send_mad_capabilities(hostdata);
1044                 return 0;
1045         }
1046
1047         evt_struct = get_event_struct(&hostdata->pool);
1048         BUG_ON(!evt_struct);
1049
1050         init_event_struct(evt_struct, fast_fail_rsp, VIOSRP_MAD_FORMAT, info_timeout);
1051
1052         fast_fail_mad = &evt_struct->iu.mad.fast_fail;
1053         memset(fast_fail_mad, 0, sizeof(*fast_fail_mad));
1054         fast_fail_mad->common.type = VIOSRP_ENABLE_FAST_FAIL;
1055         fast_fail_mad->common.length = sizeof(*fast_fail_mad);
1056
1057         spin_lock_irqsave(hostdata->host->host_lock, flags);
1058         rc = ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2);
1059         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1060         return rc;
1061 }
1062
1063 /**
1064  * adapter_info_rsp: - Handle response to MAD adapter info request
1065  * @evt_struct: srp_event_struct with the response
1066  *
1067  * Used as a "done" callback by when sending adapter_info. Gets called
1068  * by ibmvscsi_handle_crq()
1069 */
1070 static void adapter_info_rsp(struct srp_event_struct *evt_struct)
1071 {
1072         struct ibmvscsi_host_data *hostdata = evt_struct->hostdata;
1073
1074         if (evt_struct->xfer_iu->mad.adapter_info.common.status) {
1075                 dev_err(hostdata->dev, "error %d getting adapter info\n",
1076                         evt_struct->xfer_iu->mad.adapter_info.common.status);
1077         } else {
1078                 dev_info(hostdata->dev, "host srp version: %s, "
1079                          "host partition %s (%d), OS %d, max io %u\n",
1080                          hostdata->madapter_info.srp_version,
1081                          hostdata->madapter_info.partition_name,
1082                          hostdata->madapter_info.partition_number,
1083                          hostdata->madapter_info.os_type,
1084                          hostdata->madapter_info.port_max_txu[0]);
1085
1086                 if (hostdata->madapter_info.port_max_txu[0])
1087                         hostdata->host->max_sectors =
1088                                 hostdata->madapter_info.port_max_txu[0] >> 9;
1089
1090                 if (hostdata->madapter_info.os_type == 3 &&
1091                     strcmp(hostdata->madapter_info.srp_version, "1.6a") <= 0) {
1092                         dev_err(hostdata->dev, "host (Ver. %s) doesn't support large transfers\n",
1093                                 hostdata->madapter_info.srp_version);
1094                         dev_err(hostdata->dev, "limiting scatterlists to %d\n",
1095                                 MAX_INDIRECT_BUFS);
1096                         hostdata->host->sg_tablesize = MAX_INDIRECT_BUFS;
1097                 }
1098
1099                 if (hostdata->madapter_info.os_type == 3) {
1100                         enable_fast_fail(hostdata);
1101                         return;
1102                 }
1103         }
1104
1105         send_srp_login(hostdata);
1106 }
1107
1108 /**
1109  * send_mad_adapter_info: - Sends the mad adapter info request
1110  *      and stores the result so it can be retrieved with
1111  *      sysfs.  We COULD consider causing a failure if the
1112  *      returned SRP version doesn't match ours.
1113  * @hostdata:   ibmvscsi_host_data of host
1114  *
1115  * Returns zero if successful.
1116 */
1117 static void send_mad_adapter_info(struct ibmvscsi_host_data *hostdata)
1118 {
1119         struct viosrp_adapter_info *req;
1120         struct srp_event_struct *evt_struct;
1121         unsigned long flags;
1122
1123         evt_struct = get_event_struct(&hostdata->pool);
1124         BUG_ON(!evt_struct);
1125
1126         init_event_struct(evt_struct,
1127                           adapter_info_rsp,
1128                           VIOSRP_MAD_FORMAT,
1129                           info_timeout);
1130
1131         req = &evt_struct->iu.mad.adapter_info;
1132         memset(req, 0x00, sizeof(*req));
1133
1134         req->common.type = VIOSRP_ADAPTER_INFO_TYPE;
1135         req->common.length = sizeof(hostdata->madapter_info);
1136         req->buffer = hostdata->adapter_info_addr;
1137
1138         spin_lock_irqsave(hostdata->host->host_lock, flags);
1139         if (ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2))
1140                 dev_err(hostdata->dev, "couldn't send ADAPTER_INFO_REQ!\n");
1141         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1142 };
1143
1144 /**
1145  * init_adapter: Start virtual adapter initialization sequence
1146  *
1147  */
1148 static void init_adapter(struct ibmvscsi_host_data *hostdata)
1149 {
1150         send_mad_adapter_info(hostdata);
1151 }
1152
1153 /**
1154  * sync_completion: Signal that a synchronous command has completed
1155  * Note that after returning from this call, the evt_struct is freed.
1156  * the caller waiting on this completion shouldn't touch the evt_struct
1157  * again.
1158  */
1159 static void sync_completion(struct srp_event_struct *evt_struct)
1160 {
1161         /* copy the response back */
1162         if (evt_struct->sync_srp)
1163                 *evt_struct->sync_srp = *evt_struct->xfer_iu;
1164
1165         complete(&evt_struct->comp);
1166 }
1167
1168 /**
1169  * ibmvscsi_abort: Abort a command...from scsi host template
1170  * send this over to the server and wait synchronously for the response
1171  */
1172 static int ibmvscsi_eh_abort_handler(struct scsi_cmnd *cmd)
1173 {
1174         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
1175         struct srp_tsk_mgmt *tsk_mgmt;
1176         struct srp_event_struct *evt;
1177         struct srp_event_struct *tmp_evt, *found_evt;
1178         union viosrp_iu srp_rsp;
1179         int rsp_rc;
1180         unsigned long flags;
1181         u16 lun = lun_from_dev(cmd->device);
1182         unsigned long wait_switch = 0;
1183
1184         /* First, find this command in our sent list so we can figure
1185          * out the correct tag
1186          */
1187         spin_lock_irqsave(hostdata->host->host_lock, flags);
1188         wait_switch = jiffies + (init_timeout * HZ);
1189         do {
1190                 found_evt = NULL;
1191                 list_for_each_entry(tmp_evt, &hostdata->sent, list) {
1192                         if (tmp_evt->cmnd == cmd) {
1193                                 found_evt = tmp_evt;
1194                                 break;
1195                         }
1196                 }
1197
1198                 if (!found_evt) {
1199                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1200                         return SUCCESS;
1201                 }
1202
1203                 evt = get_event_struct(&hostdata->pool);
1204                 if (evt == NULL) {
1205                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1206                         sdev_printk(KERN_ERR, cmd->device,
1207                                 "failed to allocate abort event\n");
1208                         return FAILED;
1209                 }
1210
1211                 init_event_struct(evt,
1212                                   sync_completion,
1213                                   VIOSRP_SRP_FORMAT,
1214                                   abort_timeout);
1215
1216                 tsk_mgmt = &evt->iu.srp.tsk_mgmt;
1217
1218                 /* Set up an abort SRP command */
1219                 memset(tsk_mgmt, 0x00, sizeof(*tsk_mgmt));
1220                 tsk_mgmt->opcode = SRP_TSK_MGMT;
1221                 tsk_mgmt->lun = ((u64) lun) << 48;
1222                 tsk_mgmt->tsk_mgmt_func = SRP_TSK_ABORT_TASK;
1223                 tsk_mgmt->task_tag = (u64) found_evt;
1224
1225                 evt->sync_srp = &srp_rsp;
1226
1227                 init_completion(&evt->comp);
1228                 rsp_rc = ibmvscsi_send_srp_event(evt, hostdata, abort_timeout * 2);
1229
1230                 if (rsp_rc != SCSI_MLQUEUE_HOST_BUSY)
1231                         break;
1232
1233                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1234                 msleep(10);
1235                 spin_lock_irqsave(hostdata->host->host_lock, flags);
1236         } while (time_before(jiffies, wait_switch));
1237
1238         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1239
1240         if (rsp_rc != 0) {
1241                 sdev_printk(KERN_ERR, cmd->device,
1242                             "failed to send abort() event. rc=%d\n", rsp_rc);
1243                 return FAILED;
1244         }
1245
1246         sdev_printk(KERN_INFO, cmd->device,
1247                     "aborting command. lun 0x%llx, tag 0x%llx\n",
1248                     (((u64) lun) << 48), (u64) found_evt);
1249
1250         wait_for_completion(&evt->comp);
1251
1252         /* make sure we got a good response */
1253         if (unlikely(srp_rsp.srp.rsp.opcode != SRP_RSP)) {
1254                 if (printk_ratelimit())
1255                         sdev_printk(KERN_WARNING, cmd->device, "abort bad SRP RSP type %d\n",
1256                                     srp_rsp.srp.rsp.opcode);
1257                 return FAILED;
1258         }
1259
1260         if (srp_rsp.srp.rsp.flags & SRP_RSP_FLAG_RSPVALID)
1261                 rsp_rc = *((int *)srp_rsp.srp.rsp.data);
1262         else
1263                 rsp_rc = srp_rsp.srp.rsp.status;
1264
1265         if (rsp_rc) {
1266                 if (printk_ratelimit())
1267                         sdev_printk(KERN_WARNING, cmd->device,
1268                                     "abort code %d for task tag 0x%llx\n",
1269                                     rsp_rc, tsk_mgmt->task_tag);
1270                 return FAILED;
1271         }
1272
1273         /* Because we dropped the spinlock above, it's possible
1274          * The event is no longer in our list.  Make sure it didn't
1275          * complete while we were aborting
1276          */
1277         spin_lock_irqsave(hostdata->host->host_lock, flags);
1278         found_evt = NULL;
1279         list_for_each_entry(tmp_evt, &hostdata->sent, list) {
1280                 if (tmp_evt->cmnd == cmd) {
1281                         found_evt = tmp_evt;
1282                         break;
1283                 }
1284         }
1285
1286         if (found_evt == NULL) {
1287                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1288                 sdev_printk(KERN_INFO, cmd->device, "aborted task tag 0x%llx completed\n",
1289                             tsk_mgmt->task_tag);
1290                 return SUCCESS;
1291         }
1292
1293         sdev_printk(KERN_INFO, cmd->device, "successfully aborted task tag 0x%llx\n",
1294                     tsk_mgmt->task_tag);
1295
1296         cmd->result = (DID_ABORT << 16);
1297         list_del(&found_evt->list);
1298         unmap_cmd_data(&found_evt->iu.srp.cmd, found_evt,
1299                        found_evt->hostdata->dev);
1300         free_event_struct(&found_evt->hostdata->pool, found_evt);
1301         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1302         atomic_inc(&hostdata->request_limit);
1303         return SUCCESS;
1304 }
1305
1306 /**
1307  * ibmvscsi_eh_device_reset_handler: Reset a single LUN...from scsi host
1308  * template send this over to the server and wait synchronously for the
1309  * response
1310  */
1311 static int ibmvscsi_eh_device_reset_handler(struct scsi_cmnd *cmd)
1312 {
1313         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
1314         struct srp_tsk_mgmt *tsk_mgmt;
1315         struct srp_event_struct *evt;
1316         struct srp_event_struct *tmp_evt, *pos;
1317         union viosrp_iu srp_rsp;
1318         int rsp_rc;
1319         unsigned long flags;
1320         u16 lun = lun_from_dev(cmd->device);
1321         unsigned long wait_switch = 0;
1322
1323         spin_lock_irqsave(hostdata->host->host_lock, flags);
1324         wait_switch = jiffies + (init_timeout * HZ);
1325         do {
1326                 evt = get_event_struct(&hostdata->pool);
1327                 if (evt == NULL) {
1328                         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1329                         sdev_printk(KERN_ERR, cmd->device,
1330                                 "failed to allocate reset event\n");
1331                         return FAILED;
1332                 }
1333
1334                 init_event_struct(evt,
1335                                   sync_completion,
1336                                   VIOSRP_SRP_FORMAT,
1337                                   reset_timeout);
1338
1339                 tsk_mgmt = &evt->iu.srp.tsk_mgmt;
1340
1341                 /* Set up a lun reset SRP command */
1342                 memset(tsk_mgmt, 0x00, sizeof(*tsk_mgmt));
1343                 tsk_mgmt->opcode = SRP_TSK_MGMT;
1344                 tsk_mgmt->lun = ((u64) lun) << 48;
1345                 tsk_mgmt->tsk_mgmt_func = SRP_TSK_LUN_RESET;
1346
1347                 evt->sync_srp = &srp_rsp;
1348
1349                 init_completion(&evt->comp);
1350                 rsp_rc = ibmvscsi_send_srp_event(evt, hostdata, reset_timeout * 2);
1351
1352                 if (rsp_rc != SCSI_MLQUEUE_HOST_BUSY)
1353                         break;
1354
1355                 spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1356                 msleep(10);
1357                 spin_lock_irqsave(hostdata->host->host_lock, flags);
1358         } while (time_before(jiffies, wait_switch));
1359
1360         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1361
1362         if (rsp_rc != 0) {
1363                 sdev_printk(KERN_ERR, cmd->device,
1364                             "failed to send reset event. rc=%d\n", rsp_rc);
1365                 return FAILED;
1366         }
1367
1368         sdev_printk(KERN_INFO, cmd->device, "resetting device. lun 0x%llx\n",
1369                     (((u64) lun) << 48));
1370
1371         wait_for_completion(&evt->comp);
1372
1373         /* make sure we got a good response */
1374         if (unlikely(srp_rsp.srp.rsp.opcode != SRP_RSP)) {
1375                 if (printk_ratelimit())
1376                         sdev_printk(KERN_WARNING, cmd->device, "reset bad SRP RSP type %d\n",
1377                                     srp_rsp.srp.rsp.opcode);
1378                 return FAILED;
1379         }
1380
1381         if (srp_rsp.srp.rsp.flags & SRP_RSP_FLAG_RSPVALID)
1382                 rsp_rc = *((int *)srp_rsp.srp.rsp.data);
1383         else
1384                 rsp_rc = srp_rsp.srp.rsp.status;
1385
1386         if (rsp_rc) {
1387                 if (printk_ratelimit())
1388                         sdev_printk(KERN_WARNING, cmd->device,
1389                                     "reset code %d for task tag 0x%llx\n",
1390                                     rsp_rc, tsk_mgmt->task_tag);
1391                 return FAILED;
1392         }
1393
1394         /* We need to find all commands for this LUN that have not yet been
1395          * responded to, and fail them with DID_RESET
1396          */
1397         spin_lock_irqsave(hostdata->host->host_lock, flags);
1398         list_for_each_entry_safe(tmp_evt, pos, &hostdata->sent, list) {
1399                 if ((tmp_evt->cmnd) && (tmp_evt->cmnd->device == cmd->device)) {
1400                         if (tmp_evt->cmnd)
1401                                 tmp_evt->cmnd->result = (DID_RESET << 16);
1402                         list_del(&tmp_evt->list);
1403                         unmap_cmd_data(&tmp_evt->iu.srp.cmd, tmp_evt,
1404                                        tmp_evt->hostdata->dev);
1405                         free_event_struct(&tmp_evt->hostdata->pool,
1406                                                    tmp_evt);
1407                         atomic_inc(&hostdata->request_limit);
1408                         if (tmp_evt->cmnd_done)
1409                                 tmp_evt->cmnd_done(tmp_evt->cmnd);
1410                         else if (tmp_evt->done)
1411                                 tmp_evt->done(tmp_evt);
1412                 }
1413         }
1414         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1415         return SUCCESS;
1416 }
1417
1418 /**
1419  * ibmvscsi_eh_host_reset_handler - Reset the connection to the server
1420  * @cmd:        struct scsi_cmnd having problems
1421 */
1422 static int ibmvscsi_eh_host_reset_handler(struct scsi_cmnd *cmd)
1423 {
1424         unsigned long wait_switch = 0;
1425         struct ibmvscsi_host_data *hostdata = shost_priv(cmd->device->host);
1426
1427         dev_err(hostdata->dev, "Resetting connection due to error recovery\n");
1428
1429         ibmvscsi_reset_host(hostdata);
1430
1431         for (wait_switch = jiffies + (init_timeout * HZ);
1432              time_before(jiffies, wait_switch) &&
1433                      atomic_read(&hostdata->request_limit) < 2;) {
1434
1435                 msleep(10);
1436         }
1437
1438         if (atomic_read(&hostdata->request_limit) <= 0)
1439                 return FAILED;
1440
1441         return SUCCESS;
1442 }
1443
1444 /**
1445  * ibmvscsi_handle_crq: - Handles and frees received events in the CRQ
1446  * @crq:        Command/Response queue
1447  * @hostdata:   ibmvscsi_host_data of host
1448  *
1449 */
1450 void ibmvscsi_handle_crq(struct viosrp_crq *crq,
1451                          struct ibmvscsi_host_data *hostdata)
1452 {
1453         long rc;
1454         unsigned long flags;
1455         struct srp_event_struct *evt_struct =
1456             (struct srp_event_struct *)crq->IU_data_ptr;
1457         switch (crq->valid) {
1458         case 0xC0:              /* initialization */
1459                 switch (crq->format) {
1460                 case 0x01:      /* Initialization message */
1461                         dev_info(hostdata->dev, "partner initialized\n");
1462                         /* Send back a response */
1463                         if ((rc = ibmvscsi_ops->send_crq(hostdata,
1464                                                          0xC002000000000000LL, 0)) == 0) {
1465                                 /* Now login */
1466                                 init_adapter(hostdata);
1467                         } else {
1468                                 dev_err(hostdata->dev, "Unable to send init rsp. rc=%ld\n", rc);
1469                         }
1470
1471                         break;
1472                 case 0x02:      /* Initialization response */
1473                         dev_info(hostdata->dev, "partner initialization complete\n");
1474
1475                         /* Now login */
1476                         init_adapter(hostdata);
1477                         break;
1478                 default:
1479                         dev_err(hostdata->dev, "unknown crq message type: %d\n", crq->format);
1480                 }
1481                 return;
1482         case 0xFF:      /* Hypervisor telling us the connection is closed */
1483                 scsi_block_requests(hostdata->host);
1484                 atomic_set(&hostdata->request_limit, 0);
1485                 if (crq->format == 0x06) {
1486                         /* We need to re-setup the interpartition connection */
1487                         dev_info(hostdata->dev, "Re-enabling adapter!\n");
1488                         hostdata->client_migrated = 1;
1489                         purge_requests(hostdata, DID_REQUEUE);
1490                         if ((ibmvscsi_ops->reenable_crq_queue(&hostdata->queue,
1491                                                               hostdata)) ||
1492                             (ibmvscsi_ops->send_crq(hostdata,
1493                                                     0xC001000000000000LL, 0))) {
1494                                         atomic_set(&hostdata->request_limit,
1495                                                    -1);
1496                                         dev_err(hostdata->dev, "error after enable\n");
1497                         }
1498                 } else {
1499                         dev_err(hostdata->dev, "Virtual adapter failed rc %d!\n",
1500                                 crq->format);
1501
1502                         purge_requests(hostdata, DID_ERROR);
1503                         if ((ibmvscsi_ops->reset_crq_queue(&hostdata->queue,
1504                                                            hostdata)) ||
1505                             (ibmvscsi_ops->send_crq(hostdata,
1506                                                     0xC001000000000000LL, 0))) {
1507                                         atomic_set(&hostdata->request_limit,
1508                                                    -1);
1509                                         dev_err(hostdata->dev, "error after reset\n");
1510                         }
1511                 }
1512                 scsi_unblock_requests(hostdata->host);
1513                 return;
1514         case 0x80:              /* real payload */
1515                 break;
1516         default:
1517                 dev_err(hostdata->dev, "got an invalid message type 0x%02x\n",
1518                         crq->valid);
1519                 return;
1520         }
1521
1522         /* The only kind of payload CRQs we should get are responses to
1523          * things we send. Make sure this response is to something we
1524          * actually sent
1525          */
1526         if (!valid_event_struct(&hostdata->pool, evt_struct)) {
1527                 dev_err(hostdata->dev, "returned correlation_token 0x%p is invalid!\n",
1528                        (void *)crq->IU_data_ptr);
1529                 return;
1530         }
1531
1532         if (atomic_read(&evt_struct->free)) {
1533                 dev_err(hostdata->dev, "received duplicate correlation_token 0x%p!\n",
1534                         (void *)crq->IU_data_ptr);
1535                 return;
1536         }
1537
1538         if (crq->format == VIOSRP_SRP_FORMAT)
1539                 atomic_add(evt_struct->xfer_iu->srp.rsp.req_lim_delta,
1540                            &hostdata->request_limit);
1541
1542         del_timer(&evt_struct->timer);
1543
1544         if ((crq->status != VIOSRP_OK && crq->status != VIOSRP_OK2) && evt_struct->cmnd)
1545                 evt_struct->cmnd->result = DID_ERROR << 16;
1546         if (evt_struct->done)
1547                 evt_struct->done(evt_struct);
1548         else
1549                 dev_err(hostdata->dev, "returned done() is NULL; not running it!\n");
1550
1551         /*
1552          * Lock the host_lock before messing with these structures, since we
1553          * are running in a task context
1554          */
1555         spin_lock_irqsave(evt_struct->hostdata->host->host_lock, flags);
1556         list_del(&evt_struct->list);
1557         free_event_struct(&evt_struct->hostdata->pool, evt_struct);
1558         spin_unlock_irqrestore(evt_struct->hostdata->host->host_lock, flags);
1559 }
1560
1561 /**
1562  * ibmvscsi_get_host_config: Send the command to the server to get host
1563  * configuration data.  The data is opaque to us.
1564  */
1565 static int ibmvscsi_do_host_config(struct ibmvscsi_host_data *hostdata,
1566                                    unsigned char *buffer, int length)
1567 {
1568         struct viosrp_host_config *host_config;
1569         struct srp_event_struct *evt_struct;
1570         unsigned long flags;
1571         dma_addr_t addr;
1572         int rc;
1573
1574         evt_struct = get_event_struct(&hostdata->pool);
1575         if (!evt_struct) {
1576                 dev_err(hostdata->dev, "couldn't allocate event for HOST_CONFIG!\n");
1577                 return -1;
1578         }
1579
1580         init_event_struct(evt_struct,
1581                           sync_completion,
1582                           VIOSRP_MAD_FORMAT,
1583                           info_timeout);
1584
1585         host_config = &evt_struct->iu.mad.host_config;
1586
1587         /* Set up a lun reset SRP command */
1588         memset(host_config, 0x00, sizeof(*host_config));
1589         host_config->common.type = VIOSRP_HOST_CONFIG_TYPE;
1590         host_config->common.length = length;
1591         host_config->buffer = addr = dma_map_single(hostdata->dev, buffer,
1592                                                     length,
1593                                                     DMA_BIDIRECTIONAL);
1594
1595         if (dma_mapping_error(hostdata->dev, host_config->buffer)) {
1596                 if (!firmware_has_feature(FW_FEATURE_CMO))
1597                         dev_err(hostdata->dev,
1598                                 "dma_mapping error getting host config\n");
1599                 free_event_struct(&hostdata->pool, evt_struct);
1600                 return -1;
1601         }
1602
1603         init_completion(&evt_struct->comp);
1604         spin_lock_irqsave(hostdata->host->host_lock, flags);
1605         rc = ibmvscsi_send_srp_event(evt_struct, hostdata, info_timeout * 2);
1606         spin_unlock_irqrestore(hostdata->host->host_lock, flags);
1607         if (rc == 0)
1608                 wait_for_completion(&evt_struct->comp);
1609         dma_unmap_single(hostdata->dev, addr, length, DMA_BIDIRECTIONAL);
1610
1611         return rc;
1612 }
1613
1614 /**
1615  * ibmvscsi_slave_configure: Set the "allow_restart" flag for each disk.
1616  * @sdev:       struct scsi_device device to configure
1617  *
1618  * Enable allow_restart for a device if it is a disk.  Adjust the
1619  * queue_depth here also as is required by the documentation for
1620  * struct scsi_host_template.
1621  */
1622 static int ibmvscsi_slave_configure(struct scsi_device *sdev)
1623 {
1624         struct Scsi_Host *shost = sdev->host;
1625         unsigned long lock_flags = 0;
1626
1627         spin_lock_irqsave(shost->host_lock, lock_flags);
1628         if (sdev->type == TYPE_DISK) {
1629                 sdev->allow_restart = 1;
1630                 blk_queue_rq_timeout(sdev->request_queue, 120 * HZ);
1631         }
1632         scsi_adjust_queue_depth(sdev, 0, shost->cmd_per_lun);
1633         spin_unlock_irqrestore(shost->host_lock, lock_flags);
1634         return 0;
1635 }
1636
1637 /**
1638  * ibmvscsi_change_queue_depth - Change the device's queue depth
1639  * @sdev:       scsi device struct
1640  * @qdepth:     depth to set
1641  *
1642  * Return value:
1643  *      actual depth set
1644  **/
1645 static int ibmvscsi_change_queue_depth(struct scsi_device *sdev, int qdepth)
1646 {
1647         if (qdepth > IBMVSCSI_MAX_CMDS_PER_LUN)
1648                 qdepth = IBMVSCSI_MAX_CMDS_PER_LUN;
1649
1650         scsi_adjust_queue_depth(sdev, 0, qdepth);
1651         return sdev->queue_depth;
1652 }
1653
1654 /* ------------------------------------------------------------
1655  * sysfs attributes
1656  */
1657 static ssize_t show_host_vhost_loc(struct device *dev,
1658                                    struct device_attribute *attr, char *buf)
1659 {
1660         struct Scsi_Host *shost = class_to_shost(dev);
1661         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1662         int len;
1663
1664         len = snprintf(buf, sizeof(hostdata->caps.loc), "%s\n",
1665                        hostdata->caps.loc);
1666         return len;
1667 }
1668
1669 static struct device_attribute ibmvscsi_host_vhost_loc = {
1670         .attr = {
1671                  .name = "vhost_loc",
1672                  .mode = S_IRUGO,
1673                  },
1674         .show = show_host_vhost_loc,
1675 };
1676
1677 static ssize_t show_host_vhost_name(struct device *dev,
1678                                     struct device_attribute *attr, char *buf)
1679 {
1680         struct Scsi_Host *shost = class_to_shost(dev);
1681         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1682         int len;
1683
1684         len = snprintf(buf, sizeof(hostdata->caps.name), "%s\n",
1685                        hostdata->caps.name);
1686         return len;
1687 }
1688
1689 static struct device_attribute ibmvscsi_host_vhost_name = {
1690         .attr = {
1691                  .name = "vhost_name",
1692                  .mode = S_IRUGO,
1693                  },
1694         .show = show_host_vhost_name,
1695 };
1696
1697 static ssize_t show_host_srp_version(struct device *dev,
1698                                      struct device_attribute *attr, char *buf)
1699 {
1700         struct Scsi_Host *shost = class_to_shost(dev);
1701         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1702         int len;
1703
1704         len = snprintf(buf, PAGE_SIZE, "%s\n",
1705                        hostdata->madapter_info.srp_version);
1706         return len;
1707 }
1708
1709 static struct device_attribute ibmvscsi_host_srp_version = {
1710         .attr = {
1711                  .name = "srp_version",
1712                  .mode = S_IRUGO,
1713                  },
1714         .show = show_host_srp_version,
1715 };
1716
1717 static ssize_t show_host_partition_name(struct device *dev,
1718                                         struct device_attribute *attr,
1719                                         char *buf)
1720 {
1721         struct Scsi_Host *shost = class_to_shost(dev);
1722         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1723         int len;
1724
1725         len = snprintf(buf, PAGE_SIZE, "%s\n",
1726                        hostdata->madapter_info.partition_name);
1727         return len;
1728 }
1729
1730 static struct device_attribute ibmvscsi_host_partition_name = {
1731         .attr = {
1732                  .name = "partition_name",
1733                  .mode = S_IRUGO,
1734                  },
1735         .show = show_host_partition_name,
1736 };
1737
1738 static ssize_t show_host_partition_number(struct device *dev,
1739                                           struct device_attribute *attr,
1740                                           char *buf)
1741 {
1742         struct Scsi_Host *shost = class_to_shost(dev);
1743         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1744         int len;
1745
1746         len = snprintf(buf, PAGE_SIZE, "%d\n",
1747                        hostdata->madapter_info.partition_number);
1748         return len;
1749 }
1750
1751 static struct device_attribute ibmvscsi_host_partition_number = {
1752         .attr = {
1753                  .name = "partition_number",
1754                  .mode = S_IRUGO,
1755                  },
1756         .show = show_host_partition_number,
1757 };
1758
1759 static ssize_t show_host_mad_version(struct device *dev,
1760                                      struct device_attribute *attr, char *buf)
1761 {
1762         struct Scsi_Host *shost = class_to_shost(dev);
1763         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1764         int len;
1765
1766         len = snprintf(buf, PAGE_SIZE, "%d\n",
1767                        hostdata->madapter_info.mad_version);
1768         return len;
1769 }
1770
1771 static struct device_attribute ibmvscsi_host_mad_version = {
1772         .attr = {
1773                  .name = "mad_version",
1774                  .mode = S_IRUGO,
1775                  },
1776         .show = show_host_mad_version,
1777 };
1778
1779 static ssize_t show_host_os_type(struct device *dev,
1780                                  struct device_attribute *attr, char *buf)
1781 {
1782         struct Scsi_Host *shost = class_to_shost(dev);
1783         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1784         int len;
1785
1786         len = snprintf(buf, PAGE_SIZE, "%d\n", hostdata->madapter_info.os_type);
1787         return len;
1788 }
1789
1790 static struct device_attribute ibmvscsi_host_os_type = {
1791         .attr = {
1792                  .name = "os_type",
1793                  .mode = S_IRUGO,
1794                  },
1795         .show = show_host_os_type,
1796 };
1797
1798 static ssize_t show_host_config(struct device *dev,
1799                                 struct device_attribute *attr, char *buf)
1800 {
1801         struct Scsi_Host *shost = class_to_shost(dev);
1802         struct ibmvscsi_host_data *hostdata = shost_priv(shost);
1803
1804         /* returns null-terminated host config data */
1805         if (ibmvscsi_do_host_config(hostdata, buf, PAGE_SIZE) == 0)
1806                 return strlen(buf);
1807         else
1808                 return 0;
1809 }
1810
1811 static struct device_attribute ibmvscsi_host_config = {
1812         .attr = {
1813                  .name = "config",
1814                  .mode = S_IRUGO,
1815                  },
1816         .show = show_host_config,
1817 };
1818
1819 static struct device_attribute *ibmvscsi_attrs[] = {
1820         &ibmvscsi_host_vhost_loc,
1821         &ibmvscsi_host_vhost_name,
1822         &ibmvscsi_host_srp_version,
1823         &ibmvscsi_host_partition_name,
1824         &ibmvscsi_host_partition_number,
1825         &ibmvscsi_host_mad_version,
1826         &ibmvscsi_host_os_type,
1827         &ibmvscsi_host_config,
1828         NULL
1829 };
1830
1831 /* ------------------------------------------------------------
1832  * SCSI driver registration
1833  */
1834 static struct scsi_host_template driver_template = {
1835         .module = THIS_MODULE,
1836         .name = "IBM POWER Virtual SCSI Adapter " IBMVSCSI_VERSION,
1837         .proc_name = "ibmvscsi",
1838         .queuecommand = ibmvscsi_queuecommand,
1839         .eh_abort_handler = ibmvscsi_eh_abort_handler,
1840         .eh_device_reset_handler = ibmvscsi_eh_device_reset_handler,
1841         .eh_host_reset_handler = ibmvscsi_eh_host_reset_handler,
1842         .slave_configure = ibmvscsi_slave_configure,
1843         .change_queue_depth = ibmvscsi_change_queue_depth,
1844         .cmd_per_lun = IBMVSCSI_CMDS_PER_LUN_DEFAULT,
1845         .can_queue = IBMVSCSI_MAX_REQUESTS_DEFAULT,
1846         .this_id = -1,
1847         .sg_tablesize = SG_ALL,
1848         .use_clustering = ENABLE_CLUSTERING,
1849         .shost_attrs = ibmvscsi_attrs,
1850 };
1851
1852 /**
1853  * ibmvscsi_get_desired_dma - Calculate IO memory desired by the driver
1854  *
1855  * @vdev: struct vio_dev for the device whose desired IO mem is to be returned
1856  *
1857  * Return value:
1858  *      Number of bytes of IO data the driver will need to perform well.
1859  */
1860 static unsigned long ibmvscsi_get_desired_dma(struct vio_dev *vdev)
1861 {
1862         /* iu_storage data allocated in initialize_event_pool */
1863         unsigned long desired_io = max_events * sizeof(union viosrp_iu);
1864
1865         /* add io space for sg data */
1866         desired_io += (IBMVSCSI_MAX_SECTORS_DEFAULT * 512 *
1867                              IBMVSCSI_CMDS_PER_LUN_DEFAULT);
1868
1869         return desired_io;
1870 }
1871
1872 /**
1873  * Called by bus code for each adapter
1874  */
1875 static int ibmvscsi_probe(struct vio_dev *vdev, const struct vio_device_id *id)
1876 {
1877         struct ibmvscsi_host_data *hostdata;
1878         struct Scsi_Host *host;
1879         struct device *dev = &vdev->dev;
1880         struct srp_rport_identifiers ids;
1881         struct srp_rport *rport;
1882         unsigned long wait_switch = 0;
1883         int rc;
1884
1885         dev_set_drvdata(&vdev->dev, NULL);
1886
1887         host = scsi_host_alloc(&driver_template, sizeof(*hostdata));
1888         if (!host) {
1889                 dev_err(&vdev->dev, "couldn't allocate host data\n");
1890                 goto scsi_host_alloc_failed;
1891         }
1892
1893         host->transportt = ibmvscsi_transport_template;
1894         hostdata = shost_priv(host);
1895         memset(hostdata, 0x00, sizeof(*hostdata));
1896         INIT_LIST_HEAD(&hostdata->sent);
1897         hostdata->host = host;
1898         hostdata->dev = dev;
1899         atomic_set(&hostdata->request_limit, -1);
1900         hostdata->host->max_sectors = IBMVSCSI_MAX_SECTORS_DEFAULT;
1901
1902         if (map_persist_bufs(hostdata)) {
1903                 dev_err(&vdev->dev, "couldn't map persistent buffers\n");
1904                 goto persist_bufs_failed;
1905         }
1906
1907         rc = ibmvscsi_ops->init_crq_queue(&hostdata->queue, hostdata, max_events);
1908         if (rc != 0 && rc != H_RESOURCE) {
1909                 dev_err(&vdev->dev, "couldn't initialize crq. rc=%d\n", rc);
1910                 goto init_crq_failed;
1911         }
1912         if (initialize_event_pool(&hostdata->pool, max_events, hostdata) != 0) {
1913                 dev_err(&vdev->dev, "couldn't initialize event pool\n");
1914                 goto init_pool_failed;
1915         }
1916
1917         host->max_lun = 8;
1918         host->max_id = max_id;
1919         host->max_channel = max_channel;
1920         host->max_cmd_len = 16;
1921
1922         if (scsi_add_host(hostdata->host, hostdata->dev))
1923                 goto add_host_failed;
1924
1925         /* we don't have a proper target_port_id so let's use the fake one */
1926         memcpy(ids.port_id, hostdata->madapter_info.partition_name,
1927                sizeof(ids.port_id));
1928         ids.roles = SRP_RPORT_ROLE_TARGET;
1929         rport = srp_rport_add(host, &ids);
1930         if (IS_ERR(rport))
1931                 goto add_srp_port_failed;
1932
1933         /* Try to send an initialization message.  Note that this is allowed
1934          * to fail if the other end is not acive.  In that case we don't
1935          * want to scan
1936          */
1937         if (ibmvscsi_ops->send_crq(hostdata, 0xC001000000000000LL, 0) == 0
1938             || rc == H_RESOURCE) {
1939                 /*
1940                  * Wait around max init_timeout secs for the adapter to finish
1941                  * initializing. When we are done initializing, we will have a
1942                  * valid request_limit.  We don't want Linux scanning before
1943                  * we are ready.
1944                  */
1945                 for (wait_switch = jiffies + (init_timeout * HZ);
1946                      time_before(jiffies, wait_switch) &&
1947                      atomic_read(&hostdata->request_limit) < 2;) {
1948
1949                         msleep(10);
1950                 }
1951
1952                 /* if we now have a valid request_limit, initiate a scan */
1953                 if (atomic_read(&hostdata->request_limit) > 0)
1954                         scsi_scan_host(host);
1955         }
1956
1957         dev_set_drvdata(&vdev->dev, hostdata);
1958         return 0;
1959
1960       add_srp_port_failed:
1961         scsi_remove_host(hostdata->host);
1962       add_host_failed:
1963         release_event_pool(&hostdata->pool, hostdata);
1964       init_pool_failed:
1965         ibmvscsi_ops->release_crq_queue(&hostdata->queue, hostdata, max_events);
1966       init_crq_failed:
1967         unmap_persist_bufs(hostdata);
1968       persist_bufs_failed:
1969         scsi_host_put(host);
1970       scsi_host_alloc_failed:
1971         return -1;
1972 }
1973
1974 static int ibmvscsi_remove(struct vio_dev *vdev)
1975 {
1976         struct ibmvscsi_host_data *hostdata = dev_get_drvdata(&vdev->dev);
1977         unmap_persist_bufs(hostdata);
1978         release_event_pool(&hostdata->pool, hostdata);
1979         ibmvscsi_ops->release_crq_queue(&hostdata->queue, hostdata,
1980                                         max_events);
1981
1982         srp_remove_host(hostdata->host);
1983         scsi_remove_host(hostdata->host);
1984         scsi_host_put(hostdata->host);
1985
1986         return 0;
1987 }
1988
1989 /**
1990  * ibmvscsi_device_table: Used by vio.c to match devices in the device tree we
1991  * support.
1992  */
1993 static struct vio_device_id ibmvscsi_device_table[] __devinitdata = {
1994         {"vscsi", "IBM,v-scsi"},
1995         { "", "" }
1996 };
1997 MODULE_DEVICE_TABLE(vio, ibmvscsi_device_table);
1998
1999 static struct vio_driver ibmvscsi_driver = {
2000         .id_table = ibmvscsi_device_table,
2001         .probe = ibmvscsi_probe,
2002         .remove = ibmvscsi_remove,
2003         .get_desired_dma = ibmvscsi_get_desired_dma,
2004         .driver = {
2005                 .name = "ibmvscsi",
2006                 .owner = THIS_MODULE,
2007         }
2008 };
2009
2010 static struct srp_function_template ibmvscsi_transport_functions = {
2011 };
2012
2013 int __init ibmvscsi_module_init(void)
2014 {
2015         int ret;
2016
2017         /* Ensure we have two requests to do error recovery */
2018         driver_template.can_queue = max_requests;
2019         max_events = max_requests + 2;
2020
2021         if (firmware_has_feature(FW_FEATURE_ISERIES))
2022                 ibmvscsi_ops = &iseriesvscsi_ops;
2023         else if (firmware_has_feature(FW_FEATURE_VIO))
2024                 ibmvscsi_ops = &rpavscsi_ops;
2025         else
2026                 return -ENODEV;
2027
2028         ibmvscsi_transport_template =
2029                 srp_attach_transport(&ibmvscsi_transport_functions);
2030         if (!ibmvscsi_transport_template)
2031                 return -ENOMEM;
2032
2033         ret = vio_register_driver(&ibmvscsi_driver);
2034         if (ret)
2035                 srp_release_transport(ibmvscsi_transport_template);
2036         return ret;
2037 }
2038
2039 void __exit ibmvscsi_module_exit(void)
2040 {
2041         vio_unregister_driver(&ibmvscsi_driver);
2042         srp_release_transport(ibmvscsi_transport_template);
2043 }
2044
2045 module_init(ibmvscsi_module_init);
2046 module_exit(ibmvscsi_module_exit);